1. Field of the Invention
The present invention relates to a display device, and more particularly to a technique which is effectively applicable to a display device including a flexible printed circuit board.
2. Description of Related Art
A TFT (Thin Film Transistor) liquid crystal display module has been popularly used as a display device of a note-type personal computer, a car navigation system or the like.
FIG. 7 is a view for explaining the conventional constitution of a TFT liquid crystal module mounted in a car as the car navigation system.
In FIG. 7, symbol LCD indicates a liquid crystal display panel, symbol DRV indicates video line drive circuits (also referred to as drain drivers or source drivers), symbol GRV indicates scanning line drive circuits (also referred to as gate drivers), symbol FPC indicates a flexible printed circuit board, and symbol IFT indicates an I/F portion. The I/F portion (IFT) of the flexible printed circuit board (FPC) is a portion provided for connecting the flexible printed circuit board and a printed circuit board on which the driver circuits is mounted which is arranged on a back surface of the liquid crystal display panel (LCD), and a plurality of input terminals is formed on the I/F portion (IFT). The input terminals are electrically and mechanically connected with connectors mounted on the printed circuit board on which the driver circuits is mounted.
In the liquid crystal display module shown in FIG. 7, display data, control signals and power source voltages are inputted to the respective video line drive circuits (DRV) and the respective scanning line drive circuits (GRV) via the flexible printed circuit board (FPC). Accordingly, the number of lines formed on the flexible printed circuit board (FPC) is increased and hence, a profile size of the flexible printed circuit board (FPC) inevitably becomes large.
Further, the flexible printed circuit board (FPC) has one end thereof fixed to a peripheral portion of longitudinal one side of a glass substrate and has remaining ends thereof arranged on a back side of the backlight by folding. In such a state, when a profile size of the flexible printed circuit board (FPC) is larger than a profile size of the liquid crystal display panel (LCD), the flexible printed circuit board (FPC) projects outwardly from the liquid crystal display panel (LCD).
In such a case, it is necessary to fold the flexible printed circuit board (FPC) plural times so as to retain the flexible printed circuit board (FPC) within the profile size of the liquid crystal display panel (LCD).